As a lighting apparatus such as spot lighting in a commercial facility or a private residence, a reflector halogen lamp has been widely prevalent.
Meanwhile, importance is placed on saving power consumption and improving life in the field of spot lighting. Accordingly, research and development are carried out on technology for substituting a lighting apparatus including an LED (hereinafter “LED lighting apparatus”) for a conventional light bulb. Reflector halogen lamps are no exceptions, and a number of reflector LED lighting apparatuses have been proposed as substitutes for such reflector halogen lamps (see Patent Literatures 1 and 2).
In general, an LED produces heat when lit, and the higher the temperature of the LED is, the lower the light-emitting efficiency of the LED is. Therefore, in the practical application of an LED lighting apparatus, it is an important issue to improve heat dissipation characteristics without violating the size limitation, which requires the LED lighting apparatus to have a size attachable to existing equipment. To address the above issue, technology is proposed that utilizes a reflector LED lighting apparatus also as a heat dissipator by employing a metal reflector (see Patent Literature 3, for example). According to this technology, the heat dissipation characteristics of the reflector LED lighting apparatus are improved without violating the size limitation.